zonljmv,

Did you capture any SIP packets? I'd like to see the INVITE packets and also the SDP packets sent by your X-Lite and Ekiga.

Hi boatman,

Yes I made cap-files with tcpdump.
If you send me a Private Message with your emailaddress I will send the cap-files to that address.

Regards,
zonljmv

The INVITE packets that you noticed to sender (and recipient) are sent by Voxalot in an attempt to make a direct RTP connection between sender and recipient. I expect they would disappear if you set "Symmetric NAT Handling" yes.

As for the one way audio when using X-Lite, I don't see any evidence of it in the packet logs. RTP packets are going both directions, from sender to recipient and also the other way. Note that RTP packets from recipient to sender are routed through Voxalot, probably because the recipient doesn't obey INVITE once the RTP path has been established. The problem may be something to do with the X-Lite creating an RTP session description that includes your LAN address. You may be able to solve the audio problem by forwarding the RTP port range on the end that hears no audio, or go into your Voxalot account settings and set "Symmetric NAT Handling" to yes.

Hi boatman,

Because sender and recipient both have global IP-addresses the following should happen.
The INVITE request from Voxalot to the recipient should contain the IP-address and portnumber of the sender in the SDP-part.
The 200 OK status from Voxalot to the sender should contain the IP-address and portnumber of the recipient in the SDP-part.
So there should not be any NAT issue.

Regards,
zonljmv

With Voxalot the call is first established with RTP media streams through Voxalot, then if certain conditions are met INVITEs are sent to each end in an attempt to shorten the audio path. This is the first INVITE for the sender, but second INVITE for recipient.

In both samples you sent me, the recipient is not redirecting RTP to sender, the result is that the recipient's RTP stream continues to pass through Voxalot on it's way to the sender.

Both samples contain RTP pacekets in both directions, and yet no sound is heard in one direction when using X-Lite. Is there a codec issue? I see "Media Attribute (a): rtpmap:0 PCMU/8000" in Session Description from ekiga, but not from X-Lite.

Hi boatman,

I've found the reason why X-Lite didn't function properly.
Because I make use of my own proxy server (siproxd) X-Lite should be set at "Use local IP address", but was mistakenly set at "Discover global address".
Thanks for your help and sorry for the inconvenience!

Regards,
zonljmv

Well, that's good news. Are RTP packets still going the same as before; one hop to recipient, and the return is two hops and through Voxalot?

Yes, the same as before.

Regards,
zonljmv

Martin,

This problem is happening again.

Thanks,
The Doc

I have restarted all proxies. Please let me know if this addresses your problem?